@@ -51,6 +51,60 @@ unsigned int get_loadparm_index(void)
return atoui(loadparm_str);
}
+static int is_dev_possibly_bootable(int dev_no, int sch_no)
+{
+ bool is_virtio;
+ Schib schib;
+ int r;
+
+ blk_schid.sch_no = sch_no;
+ r = stsch_err(blk_schid, &schib);
+ if (r == 3 || r == -EIO) {
+ return -ENODEV;
+ }
+ if (!schib.pmcw.dnv) {
+ return false;
+ }
+
+ enable_subchannel(blk_schid);
+ cutype = cu_type(blk_schid);
+
+ /*
+ * Note: we always have to run virtio_is_supported() here to make
+ * sure that the vdev.senseid data gets pre-initialized correctly
+ */
+ is_virtio = virtio_is_supported(blk_schid);
+
+ /* No specific devno given, just return whether the device is possibly bootable */
+ if (dev_no < 0) {
+ switch (cutype) {
+ case CU_TYPE_VIRTIO:
+ if (is_virtio) {
+ /*
+ * Skip net devices since no IPLB is created and therefore
+ * no network bootloader has been loaded
+ */
+ if (virtio_get_device_type() != VIRTIO_ID_NET) {
+ return true;
+ }
+ }
+ return false;
+ case CU_TYPE_DASD_3990:
+ case CU_TYPE_DASD_2107:
+ return true;
+ default:
+ return false;
+ }
+ }
+
+ /* Caller asked for a specific devno */
+ if (schib.pmcw.dev == dev_no) {
+ return true;
+ }
+
+ return false;
+}
+
/*
* Find the subchannel connected to the given device (dev_no) and fill in the
* subchannel information block (schib) with the connected subchannel's info.
@@ -62,53 +116,14 @@ unsigned int get_loadparm_index(void)
*/
static bool find_subch(int dev_no)
{
- Schib schib;
int i, r;
- bool is_virtio;
for (i = 0; i < 0x10000; i++) {
- blk_schid.sch_no = i;
- r = stsch_err(blk_schid, &schib);
- if ((r == 3) || (r == -EIO)) {
+ r = is_dev_possibly_bootable(dev_no, i);
+ if (r < 0) {
break;
}
- if (!schib.pmcw.dnv) {
- continue;
- }
-
- enable_subchannel(blk_schid);
- cutype = cu_type(blk_schid);
-
- /*
- * Note: we always have to run virtio_is_supported() here to make
- * sure that the vdev.senseid data gets pre-initialized correctly
- */
- is_virtio = virtio_is_supported(blk_schid);
-
- /* No specific devno given, just return 1st possibly bootable device */
- if (dev_no < 0) {
- switch (cutype) {
- case CU_TYPE_VIRTIO:
- if (is_virtio) {
- /*
- * Skip net devices since no IPLB is created and therefore
- * no network bootloader has been loaded
- */
- if (virtio_get_device_type() != VIRTIO_ID_NET) {
- return true;
- }
- }
- continue;
- case CU_TYPE_DASD_3990:
- case CU_TYPE_DASD_2107:
- return true;
- default:
- continue;
- }
- }
-
- /* Caller asked for a specific devno */
- if (schib.pmcw.dev == dev_no) {
+ if (r == true) {
return true;
}
}